| 摘要 |
1536748 Sintered fibre-reinforced articles WESTINGHOUSE CANADA Ltd 8 June 1976 [24 Dec 1975] 23589/76 Heading C7D A composite article is formed from a matrix material and reinforcing fibres by forming a plastics tape containing the matrix material, arranging the fibres in a regular pattern between two layers of tape, cutting the tape into a plurality of laminae, arranging the laminae into a form to reproduce the shape of the article, and subjecting to hot isostatic pressing. The method is used to produce turbine blades and other engine components from superalloys reinforced with fibres of W, Mo, SiC or graphite. Powdered superalloy is mixed with a resin, e.g. polymethacrylate, and formed into tapes 7, 8 having a plastic backing, the tapes being fed from reels 9, 10 above and below fibres 5 fed from reel 6, passing through rolls 11, which may be heated, to produce a tape containing the fibres, after which the plastic backings 16 are removed. Laminae cut from the tape are placed inside a container in the desired shape, e.g. an airfoil Figs. 3 and 4 (not shown), the container is evacuated, filled with H 2 , heated, e.g. to 300‹C, to decompose the binder, the spaces (20) are filled with superalloy powder and the whole is evacuated, sealed and hot isostatically pressed e.g. at 900-1300‹C and 10,000-30,000 psi. The container may be of steel, in which case it is removed by pickling, or of corrosion resistant alloy when it may remain as part of the article. Alternatively the container may be a ceramic mould formed by the lost wax process, which, when filled is placed in a metal container, the space between the container and ceramic mould being filled by SiO 2 or a metal halide, e.g. NaCl, BaF 2 . The composite article may be hot forged if necessary, and may be given an aluminizing coating by pack diffusion or vacuum evaporation. Superalloys containing as main ingredients Ni-W-Co-Cr-Al and Co-Cr-Mo are referred to. |
